<!doctype html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
</head>
<body>
<script>
	var str="Visit Microsoft!";
	alert(str.replace(/Visit /,""));		//	Microsoft!

var str = 'abcdef';
alert(str.replace(/b/,'\,'));		//	a,cdef
</script>	
</body>
</html>